Increased acylated plasma ghrelin, but improved lipid profiles 24-h after consumption of carob pulp preparation rich in dietary fibre and polyphenols

We have recently shown that a polyphenol-rich insoluble dietary fibre preparation from carob pulp (Ceratonia siliqua L; carob fibre) decreased postprandial acylated ghrelin, TAG and NEFA during an acute liquid meal challenge test. However, delayed effects of carob fibre consumption are unknown. Therefore, a randomized controlled crossover study in nineteen healthy volunteers consuming foods with or without 50 g carob fibre was conducted. On the subsequent day (day 2), glucose, TAG, total and acylated ghrelin as well as insulin, NEFA and leptin were assessed at baseline and at timed intervals for 300 min after ingestion of standardized bread. Consumption of carob fibre-enriched foods did not affect fasting concentrations of glucose, TAG, total ghrelin, NEFA, insulin and leptin. Fasting acylated ghrelin was increased on the day subsequent to carob fibre consumption compared with control (P = 0.046). After consumption of the standard bread on day 2, glucose response (P = 0.029) was increased, and TAG (P = 0.033) and NEFA (P < 0.001) responses were decreased compared with control. Postprandial responses of total and acylated ghrelin, insulin and leptin on day 2 were unaffected by carob fibre consumption the previous day. In conclusion, an increase in total and acylated plasma ghrelin accompanied by enhanced lipid metabolism after carob fibre consumption suggests higher lipid utilization and suppressed lipolysis on the day subsequent to carob fibre consumption. However, elevated glucose levels after carob fibre consumption need to be addressed in future studies.     

Carob pulp preparation rich in insoluble dietary fiber and polyphenols enhances lipid oxidation and lowers postprandial acylated ghrelin in humans

Ghrelin is an orexigenic hormone that may affect substrate utilization in humans. Ghrelin is influenced by macronutrients, but the effects of insoluble dietary fiber and polyphenols are unknown. We investigated the effects of a polyphenol-rich insoluble dietary fiber preparation from carob pulp (carob fiber) on postprandial ghrelin responses and substrate utilization. Dose-dependent effects of the consumption of carob fiber were investigated in a randomized, single-blind, crossover study in 20 healthy subjects, aged 22-62 y. Plasma total and acylated ghrelin, triglycerides, and serum insulin and nonesterified fatty acids (NEFA) levels were repeatedly assessed before and after ingestion of an isocaloric standardized liquid meal with 0, 5, 10, or 20 g of carob fiber over a 300-min period. The respiratory quotient (RQ) was determined after consumption of 0 or 20 g of carob fiber. Carob fiber intake lowered acylated ghrelin to 49.1%, triglycerides to 97.2%, and NEFA to 67.2% compared with the control meal (P < 0.001). Total ghrelin and insulin concentrations were not affected by consumption of a carob fiber-enriched liquid meal. Postprandial energy expenditure was increased by 42.3% and RQ was reduced by 99.9% after a liquid meal with carob fiber compared with a control meal (P < 0.001). We showed that the consumption of a carob pulp preparation, an insoluble dietary fiber rich in polyphenols, decreases postprandial responses of acylated ghrelin, triglycerides, and NEFA and alters RQ, suggesting a change toward increased fatty acid oxidation. These results indicate that carob fiber might exert beneficial effects in energy intake and body weight.     

Incorporation of lean red meat into a National Cholesterol Education Program Step I diet: a long-term, randomized clinical trial in free-living persons with hypercholesterolemia

OBJECTIVE: Clinicians often recommend that intake of all meat, particularly red meat, be reduced in conjunction with a low-fat, low-cholesterol diet to reduce low-density lipoprotein (LDL) cholesterol. This study was designed to determine the long-term effects of lean red meat (beef, veal and pork) compared to lean white meat (poultry and fish) consumption on lipoprotein concentrations in free-living hypercholesterolemic subjects consuming a National Cholesterol Education Program (NCEP) Step I diet. METHODS: A randomized, crossover design was utilized. Hypercholesterolemic men and women (LDL cholesterol between 3.37 and 4.92 mmol/L) (triglycerides <3.96 mmol/L) (n = 145) were counseled to consume > or =80% of their 170 g/d meat intake as either lean red meat or lean white meat for two 36-week phases, separated by a four-week washout period of free meat selection. Subjects were instructed to follow an NCEP Step I diet throughout the study. RESULTS: There were no significant differences in lipid concentrations between the lean red meat and lean white meat phases. LDL cholesterol was 4.02+/-0.04 (SEM) and 4.01+/-0.04 mmol/L in the white and red phases, respectively; this represented a decrease of approximately 2% from baseline concentrations (p < 0.01). Total cholesterol also declined by 1% from baseline (p < 0.05), and high-density lipoprotein (HDL) cholesterol rose over the study period by approximately 2% to approximately 3% from baseline to reach concentrations of 1.37+/-0.03 mmol/L and 1.38+/-0.03 mmol/L in the white and red phases, respectively (p < 0.001). Triglycerides were not altered by treatment. CONCLUSIONS: Consumption of lean red meat or lean white meat, as part of an NCEP Step I diet, is similarly effective for reducing LDL cholesterol and elevating HDL cholesterol concentrations in free-living persons with hypercholesterolemia.     

Incorporation of Lean Red Meat into a National Cholesterol Education Program Step I Diet: A Long-Term,Randomized Clinical Trial in Free-Living Persons with Hypercholesterolemia

Objective: Clinicians often recommend that intake of all meat, particularly red meat, be reduced in conjunction with a low-fat, low-cholesterol diet to reduce low-density lipoprotein (LDL) cholesterol. This study was designed to determine the long-term effects of lean red meat (beef, veal and pork) compared to lean white meat (poultry and fish) consumption on lipoprotein concentrations in free-living hypercholesterolemic subjects consuming a National Cholesterol Education Program (NCEP) Step I diet.

Methods: A randomized, crossover design was utilized. Hypercholesterolemic men and women (LDL cholesterol between 3.37 and 4.92 mmol/L) (triglycerides <3.96 mmol/L) (n = 145) were counseled to consume ≥80% of their 170 g/d meat intake as either lean red meat or lean white meat for two 36-week phases, separated by a four-week washout period of free meat selection. Subjects were instructed to follow an NCEP Step I diet throughout the study.

Results: There were no significant differences in lipid concentrations between the lean red meat and lean white meat phases. LDL cholesterol was 4.02 ± 0.04 (SEM) and 4.01 ± 0.04 mmol/L in the white and red phases, respectively; this represented a decrease of ～2% from baseline concentrations (p < 0.01). Total cholesterol also declined by 1% from baseline (p < 0.05), and high-density lipoprotein (HDL) cholesterol rose over the study period by ～2% to ～3% from baseline to reach concentrations of 1.37 ± 0.03 mmol/L and 1.38 ± 0.03 mmol/L in the white and red phases, respectively (p < 0.001). Triglycerides were not altered by treatment.

Conclusions: Consumption of lean red meat or lean white meat, as part of an NCEP Step I diet, is similarly effective for reducing LDL cholesterol and elevating HDL cholesterol concentrations in free-living persons with hypercholesterolemia.     

Almonds Have a Neutral Effect on Serum Lipid Profiles: A Meta-Analysis of Randomized Trials

Almond consumption may be associated with improvements in serum lipid profiles. The aim was to evaluate the influence of almonds on lipid parameters to help define the role of almonds as a lipid modulator. MEDLINE, EMBASE, Cochrane CENTRAL, and the Natural Medicines Comprehensive Database were searched through July 2008, with no language restrictions, for randomized controlled trials of almonds in human patients that reported efficacy data on at least one of the following endpoints: total, low-density lipoprotein (LDL), or high-density lipoprotein (HDL) cholesterol, triglycerides, or the LDL:HDL ratio. A manual search of references from primary or review articles was performed to identify additional relevant trials. Five randomized, controlled trials (totaling 142 participants) met all inclusion criteria. Upon meta-analysis, almond consumption ranging from 25 to 168 g/day significantly lowered total cholesterol [weighted mean difference -6.95 mg/dL (95% confidence interval [CI] −13.12 to −0.772) (−0.18 mmol/L [95% CI −0.34 to −0.02])] and showed a strong trend toward reducing LDL cholesterol [weighted mean difference -5.79 mg/dL (95% CI -11.2 to 0.00) (-0.15 mmol/L [95% CI -0.29 to 0.00])]. No significant effect on HDL cholesterol, triglycerides, or LDL:HDL ratio was found. No statistical heterogeneity was observed for any analysis (I²=0% for all). Review of funnel plots and the Egger's weighted regression statistic P values suggested a low likelihood of publication bias in all analyses (P>0.25 for all). Almond consumption may decrease total cholesterol and does not significantly affect LDL or HDL cholesterol, triglycerides, or the LDL:HDL ratio. The current body of randomized trials does not support the ingestion of almonds solely for their lipid modifying effects. Both the lipid modulating effects and the safety/tolerability of almonds should be further investigated through the conduction of larger randomized, double-blinded trials of longer duration. Such studies might focus specifically on whether the efficacy of almonds as a lipid modulator varies by dose or comorbidity.     

Lipids and lipoproteins in a young adult population. The Beaver County Lipid Study

Though atherosclerosis may have its origins in childhood, intervention studies on coronary heart disease risk factors have usually begun in older adults. Whether young adults exhibit similar relationships of lifestyle to coronary heart disease risk factors, and therefore might be suitable candidates for appropriate intervention, is poorly understood. The Beaver County Lipid Study is a 9-year follow-up study of a free-living young adult population (mean age 22 years) who were initially screened for hypercholesterolemia as seventh grade school children. This report focuses upon cross-sectional correlates of lipid and lipoprotein concentrations in 561 individuals (males n = 262; females n = 299) in 1981-1982. Body mass index was positively related to low density lipoprotein (LDL) cholesterol and triglycerides in men (r = 0.21; p less than 0.001 and r = 0.41; p less than 0.001) and women (r = 0.16; p less than 0.001 and r = 0.20; p less than 0.001). Cigarette smoking was inversely associated with high density lipoprotein (HDL) cholesterol in men (r = -0.11; p less than 0.001) and women (r = -0.20; p less than 0.001) but positively related to triglycerides in both sexes (r = 0.10; p = 0.05 for men and r = 0.19; p less than 0.01 for women). Alcohol consumption was positively related to HDL cholesterol and triglycerides only among men (r = 0.19; p less than 0.001 and r = 0.12; p less than 0.05, respectively). Educational achievement was also positively related to HDL cholesterol in men (p less than 0.01) and women (p less than 0.001). Multivariate analyses indicate that the sex difference in LDL cholesterol was largely eliminated by controlling for body mass index while significant sex differences in both HDL cholesterol and triglycerides remained after controlling for covariates. Results suggest that the known associations in older adults of body mass index and health-related behavior with lipoproteins are well established by young adulthood. Early intervention particularly for obesity may help ameliorate some of the male excess in cardiovascular disease risk.     

Lipid Responses to a Dietary Docosahexaenoic Acid Supplement in Men and Women with Below Average Levels of High Density Lipoprotein Cholesterol

Objective: To assess fasting lipid responses to a docosahexaenoic acid (DHA) supplement in men and women with below-average levels of high-density lipoprotein (HDL) cholesterol.

Methods: This randomized, double-blind, controlled clinical trial included 57 subjects, 21–80 years of age, with fasting HDL cholesterol concentrations ≤44 mg/dL (men) and ≤54 mg/dL (women), but ≥35 mg/dL. Subjects were randomly assigned to receive either 1.52 g/day DHA from capsules containing DHA-rich algal triglycerides or olive oil (control) for six weeks.

Results: There were no significant differences between groups in baseline lipid values. The DHA supplemented group showed significant changes [?43 (DHA) vs. ?14 (controls) mg/dL, p = 0.015] and percent changes [?21% (DHA) vs. ?7% (controls), p = 0.009] in triglycerides, total (12 vs. 3 mg/dL; p = 0.021 and 6% vs. 2%; p = 0.018) and low-density lipoprotein (17 vs. 3 mg/dL; p = 0.001 and 12% vs. 3%; p = 0.001) cholesterol concentrations, and in the triglyceride to HDL cholesterol ratio (?1.33 vs. ?0.50, p = 0.010), compared with controls. In addition, there was a significant reduction in the percentage of LDL cholesterol carried by small, dense particles in the DHA supplemented group (changes = ?10% vs. ?3%, p = 0.025).

Conclusions: Supplementation with 1.52 g/d of DHA in men and women with below-average HDL cholesterol concentrations raised the LDL cholesterol level, but had favorable effects on triglycerides, the triglyceride/HDL cholesterol ratio and the fraction of LDL cholesterol carried by small, dense particles. Further research is warranted to evaluate the net impact of these alterations on cardiovascular risk.     

Colonic Microbiota Profile Characterization of the Responsiveness to Dietary Fibre Treatment in Hypercholesterolemia

This study aimed to determine how the microbiota profile might be predisposed to a better response in blood lipid profiles due to dietary fibre supplementation. A three-arm intervention study that included three different fibre types (mainly insoluble, soluble, and antioxidant fibre) supplemented (19.2 g/day) during 2 months in individuals with hypercholesterolemia was developed. Changes in faecal microbiota and blood lipid profile after fibre supplementation were determined. In all volunteers, regardless of fibre type, an increase in the abundance of Bifidobacterium was observed, and similarly, an inverse relationship between faecal propionic acid and blood LDL-cholesterol, LDL particle size, and LDL/HDL particle ratio (p-values 0.0067, 0.0002, and 0.0067, respectively) was observed. However, not all volunteers presented an improvement in lipid profile. The non-responders to fibre treatment showed a decrease in microbiota diversity (Shannon and Simpson diversity index p-values of 0.0110 and 0.0255, respectively) after the intervention; where the reduction in short-chain fatty acids (SCFAs) producing bacterial genera such as Clostridium XIVa and Ruminococcus after dietary fibre treatment was the main difference. It was concluded that the non-responsiveness to dietary fibre treatment might be mediated by the lack of ability to maintain a stable SCFA producing bacteria diversity and composition after extra fibre intake.     

Effects of obesity and body fat distribution on lipids and lipoproteins in nondiabetic American Indians: The Strong Heart Study

OBJECTIVES: To examine the relationship between obesity and lipoprotein profiles and compare the effects of total obesity and central adiposity on lipids/lipoproteins in American Indians. RESEARCH METHODS AND PROCEDURES: Participants were 773 nondiabetic American Indian women and 739 men aged 45 to 74 years participating in the Strong Heart Study. Total obesity was estimated using body mass index (BMI). Central obesity was measured as waist circumference. Lipoprotein measures included triglycerides, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, apolipoprotein AI (apoAI), and apolipoprotein B (apoB). Partial and canonical correlation analyses were used to examine the associations between obesity and lipids/ lipoproteins. RESULTS: Women were more obese than men in Arizona (median BMI 32.1 vs. 29.2 kg/m2) and South Dakota and North Dakota (28.3 vs. 28.0 kg/m2), but there was no sex difference in waist circumference. Men had higher apoB and lower apoAI levels than did women. In women, when adjusted for center, gender, and age, BMI was significantly related to HDL cholesterol (r = -0.24, p < 0.001). There was a significant but weak relation with apoAI (r = -0.14, p < 0.001). Waist circumference was positively related to triglycerides (r = 0.14, p < 0.001) and negatively related to HDL cholesterol (r = -0.23, p < 0.001) and apoAI (r = -0.13, p < 0.001). In men, BMI was positively correlated with triglycerides (r = 0.30, p < 0.001) and negatively correlated with HDL cholesterol (r = -0.35, p < 0.001) and apoAI (r = -0.23, p < 0.001). Triglycerides increased with waist circumference (r = 0.30, p < 0.001) and HDL cholesterol decreased with waist circumference (r = -0.36, p < 0.001). In both women and men there was an inverted U-shaped relationship between obesity and waist with LDL cholesterol and apoB. In canonical correlation analysis, waist circumference received a greater weight (0.86) than did BMI (0.17) in women. However, the canonical weights were similar for waist (0.46) and BMI (0.56) in men. Only HDL cholesterol (-1.02) carried greater weight in women, whereas in men, triglycerides (0.50), and HDL cholesterol (-0.64) carried a large amount of weight. All the correlation coefficients between BMI, waist circumference, and the first canonical variable of lipids/lipoproteins or between the individual lipid/lipoprotein variables and the first canonical variable of obesity were smaller in women than in men. Triglycerides and HDL cholesterol showed clinically meaningful changes with BMI and waist circumference in men. All lipid/lipoprotein changes in women in relation to BMI and waist circumference were minimal. DISCUSSION: The main lipoprotein abnormality related to obesity in American Indians was decreased HDL cholesterol, especially in men. Central adiposity was more associated with abnormal lipid/lipoprotein profiles than general obesity in women; both were equally important in men.     

Effects of differing phenolic content in dietary olive oils on lipids and LDL oxidation

Summary.Background: Evidence from in vitro studies suggests that antioxidant olive oil phenolic compounds can prevent LDL oxidation. However, in vivo evidence in support of this hypothesis is sparse.Aim of the study: to establish the antioxidant effect of olive oils with differences in their phenolic compounds content in humansMethods: A controlled, double blind, cross-over, randomized, clinical trial using three similar olive oils with increasing phenolic concentration (from 0 to 150 mg/Kg) was conducted in 30 healthy volunteers. Olive oils were administered over three periods of 3 weeks preceded by two-week washout periods.Results: Urinary tyrosol and hydroxytyrosol increased (p < 0.020), in vivo plasma oxidized LDL decreased (p = 0.006), and ex vivo resistance of LDL to oxidation increased (p = 0.012) with the phenolic content of the olive oil administered. After virgin olive oil administration, an increase (p = 0.029) was observed in HDL cholesterol levels.Conclusions: Sustained consumption of virgin olive oil with the high phenolic content was more effective in protecting LDL from oxidation and in rising HDL cholesterol levels than that of other type of olive oils. Dose-dependent changes in oxidative stress markers, and phenolic compounds in urine, were observed with the phenolic content of the olive oil administered. Our results support the hypothesis that virgin olive oil consumption could provide benefits in the prevention of oxidative processes.* Participants of the SOLOS-Investigation are listed in the Appendix.     

Lipid responses to a dietary docosahexaenoic acid supplement in men and women with below average levels of high density lipoprotein cholesterol

OBJECTIVE: To assess fasting lipid responses to a docosahexaenoic acid (DHA) supplement in men and women with below-average levels of high-density lipoprotein (HDL) cholesterol. METHODS: This randomized, double-blind, controlled clinical trial included 57 subjects, 21-80 years of age, with fasting HDL cholesterol concentrations < or =44 mg/dL (men) and < or =54 mg/dL (women), but > or =35 mg/dL. Subjects were randomly assigned to receive either 1.52 g/day DHA from capsules containing DHA-rich algal triglycerides or olive oil (control) for six weeks. RESULTS: There were no significant differences between groups in baseline lipid values. The DHA supplemented group showed significant changes [-43 (DHA) vs. -14 (controls) mg/dL, p = 0.015] and percent changes [-21% (DHA) vs. -7% (controls), p = 0.009] in triglycerides, total (12 vs. 3 mg/dL; p = 0.021 and 6% vs. 2%; p = 0.018) and low-density lipoprotein (17 vs. 3 mg/dL; p = 0.001 and 12% vs. 3%; p = 0.001) cholesterol concentrations, and in the triglyceride to HDL cholesterol ratio (-1.33 vs. -0.50, p = 0.010), compared with controls. In addition, there was a significant reduction in the percentage of LDL cholesterol carried by small, dense particles in the DHA supplemented group (changes = -10% vs. -3%, p = 0.025). CONCLUSIONS: Supplementation with 1.52 g/d of DHA in men and women with below-average HDL cholesterol concentrations raised the LDL cholesterol level, but had favorable effects on triglycerides, the triglyceride/HDL cholesterol ratio and the fraction of LDL cholesterol carried by small, dense particles. Further research is warranted to evaluate the net impact of these alterations on cardiovascular risk.     

Effect of pistachio nuts on serum lipid levels in patients with moderate hypercholesterolemia.

BACKGROUND: Elevated serum cholesterol levels play an important role in the development of coronary artery disease. Previous studies have suggested that nut consumption benefits lipid profile. Pistachio nuts are widely available, inexpensive and frequently consumed by the general population. OBJECTIVE: To determine whether substituting 20% of the daily caloric intake in the form of pistachio nuts will improve the lipid profiles of humans with primary, moderate hypercholesterolemia. DESIGN: Controlled, randomized crossover design. SETTING: Outpatient dietary modification, counseling and blood analysis. PATIENTS: Ten patients with moderate hypercholesterolemia. INTERVENTION: Three weeks of dietary modification with 20% caloric intake from pistachio nuts. MEASUREMENTS: Body weight, blood pressure, total cholesterol, LDL, HDL, and triglycerides were monitored. Lipid profiles were analyzed prior to, during and after dietary modification. RESULTS: After three weeks, there was a decrease in total cholesterol (p<0.04), an increase in HDL (p<0.09), a decrease in the total cholesterol/HDL ratio (p<0.01) and a decrease in the LDL/HDL ratio (p<0.02). Triglycerides and LDL levels decreased, but not significantly. Body weight and blood pressure remained constant throughout the study. CONCLUSIONS: Results suggest that eating pistachio nuts instead of other dietary fat calories can improve lipid profiles, thereby decreasing coronary risk. Further studies will be required to confirm these results and to determine the mechanism of this effect.     

Carob pulp preparation rich in insoluble dietary fibre and polyphenols increases plasma glucose and serum insulin responses in combination with a glucose load in humans

Dietary fibre consumption is associated with improved glucose homeostasis. In contrast, dietary polyphenols have been suggested to exert both beneficial and detrimental effects on glucose and insulin metabolism. Recently, we reported that a polyphenol-rich insoluble dietary fibre preparation from carob pulp (carob fibre) resulted in lower postprandial acylated ghrelin levels after a liquid meal challenge test compared with a control meal without supplementation. The effects may, however, differ when a different food matrix is used. Thus, we investigated the effects of carob fibre on glucose, insulin and ghrelin responses in healthy humans in combination with a glucose load. In a randomized single-blind cross-over study involving twenty healthy subjects (aged 22-62 years), plasma glucose, total and acylated ghrelin, and serum insulin were repeatedly assessed before and after the ingestion of 200 ml water with 50 g glucose and 0, 5, 10 or 20 g carob fibre over a period of 180 min. The intake of 5 and 10 g carob fibre increased the plasma glucose by 47 % and 64 % (P < 0.001), and serum insulin by 19.9 and 24.8 % (P < 0.001), compared with the control. Plasma acylated ghrelin concentrations did not change significantly after the consumption of carob-enriched glucose solution. Total ghrelin decreased only after 10 g carob fibre (P < 0.001) compared with control. In conclusion, we showed that polyphenol-rich carob fibre, administered within a water-glucose solution, increases postprandial glucose and insulin responses, suggesting a deterioration in glycaemic control.     

The interaction of alcohol consumption and oral contraceptive use on lipids and lipoproteins

Oral contraceptive (OC) use and alcohol consumption have been shown to alter the levels of lipids and lipoproteins in the blood. The effect of alcohol consumption on levels of total cholesterol, LDL cholesterol, HDL cholesterol, triglycerides, LDL-B, Apo-A1, the ratio of HDL cholesterol/total cholesterol, HDL cholesterol/LDL cholesterol, and the ratio of LDL cholesterol/LDL-B among normal healthy young women before initiation of oral contraceptives and after six months of oral contraceptive use are both described. Of primary interest is the mediating effect of alcohol consumption on the association between steroid usage and blood lipid values. At baseline, ethanol consumption was found to be positively associated with triglycerides, HDL-C, and Apo-A1 and negatively associated with LDL-C/LDL-B. After adjustment for several covariables, alcohol consumption was found to be positively associated with the increases in triglycerides and in Apo-A1 observed at 3 and 6 months after initiation of OCs. Since these two parameters are believed to have opposite relationships to cardiovascular disease, the effect of alcohol consumption remains uncertain.     

Evaluation of the polychlorobiphenyl Aroclor® 1254 in an animal model of atherosclerosis

Dietary polychlorinated biphenyls (PCBs) were evaluated in an atherosclerosis animal model during a 26-week period. Male white Carneau pigeons were maintained on diets containing either 0, 5, 25, or 125 g/g Aroclor^® 1254. One-half of the birds from each of the four groups consumed diets which contained 0.5% cholesterol. Serum samples were analyzed after 8, 16, and 26 weeks of dietary treatment. Liver samples were analyzed for Zn and PCB content. Relative liver weight and serum glutamic-oxaloacetic transaminase (SGOT) increased with PCB consumption; however, liver Zn and serum alkaline phosphatase were negatively correlated with PCB exposure. Dietary cholesterol induced hypercholesterolemia, which was accounted for by elevation of serum low density lipoprotein cholesterol (LDL) and very-low density lipoprotein cholesterol (VLDL). Consumption of dietary PCBs was inversely related to serum high density lipoprotein cholesterol (HDL), The serum total cholesterol/HDL ratio was elevated by dietary cholesterol but not by PCBs. The serum HDL/LDL ratio was depressed by dietary cholesterol but not by PCBs. Chronic lowering of serum HDL associated with hypercholesterolemia and a decreased serum HDL/LDL ratio, as observed in this study, would be expected to exacerbate atherosclerosis.     

Relative contributions of genes, environment, and interactions to blood lipid concentrations in a general adult population

The authors evaluated the contributions of nine genetic (G) variants (selected from 275 single nucleotide polymorphisms in 11 reverse cholesterol transport pathway genes), five environmental (E) factors (selected from 10), and G x G, E x E, and G x E interactions in explaining population variance of blood lipid concentrations. Total cholesterol, triglycerides, and high density lipoprotein (HDL) cholesterol were measured, and low density lipoprotein (LDL) cholesterol and HDL cholesterol/LDL cholesterol ratio were calculated in a population-based random sample of 1,543 men and women in Geneva, Switzerland, aged 35-74 years in 1999-2001. Explained variances (R2) for HDL cholesterol/LDL cholesterol ratio, HDL cholesterol, and LDL cholesterol, respectively, were 34%, 33%, and 19%, decomposed into main effects of G (6%, 4%, and 5%) and E (25%, 28%, and 11%), with just 3%, 2%, and 3% due to G x G, E x E, and G x E interactions, respectively. Risk factor clustering was only moderate: 70% of study subjects had < or =3 variants, 75% had < or =2 environmental exposures, and 69% had < or =5 of both types of factors. Multiple genes with weak associations, together with more dominating environmental factors, are involved in determining blood lipid concentrations. Interactions added little explained variance. Increasing trends in hypercholesterolemia are attributable to environmental changes affecting populations as a whole. Reducing obesity and smoking and moderating alcohol intake in entire populations should remain the primary strategies for lipid control.     

Low-Density Lipoprotein Subclass Distribution Pattern and Adiposity-Associated Dyslipidemia in Postmenopausal Women

Objective: A predominance of small, dense low-density lipoprotein (LDL) particles (subclass pattern B) is associated with increased risk for coronary heart disease and is characterized by elevated triglycerides and depressed high-density lipoprotein (HDL) cholesterol concentrations. The present analysis was undertaken to assess the impact of LDL subclass distribution pattern and adiposity on serum lipids in postmenopausal women.

Methods: Anthropometric measurements and fasting lipid data were obtained from 254 postmenopausal women 70 years of age or younger, not receiving sex hormone replacement, who were participating in a clinical trial designed to assess the influence of hormone replacement regimens on coronary heart disease risk markers.

Results: The prevalence of LDL subclass pattern B was 32%. Triglyceride levels were higher and HDL cholesterol lower (both p<0.001) in women with pattern B vs. pattern A, but total and LDL cholesterol levels did not differ. LDL subclass pattern contributed independently to the variance in HDL cholesterol (p<0.001) and log_e triglyceride (p<0.001) concentrations explained by anthropometric variables (waist circumference or body mass index). Compared to women with LDL subclass pattern A and waist circumference below the median value of 83.0 centimeters, those with pattern B and waist ≥83.0 centimeters had markedly lower HDL cholesterol levels [44.0 (41.6–47.4) vs. 57.2 (54.1–60.3) mg/dL, mean (95% CI)] and increased triglyceride concentrations [geometric mean 147.8 (131.6–165.7) vs. 95.4 (88.2–102.5) mg/dL].

Conclusions: These data suggest that adiposity and LDL subclass distribution pattern are independent determinants of plasma triglyceride and HDL cholesterol concentrations in postmenopausal women.     

Alterations in lipid profile of autistic boys: a case control study

We hypothesize that autism is associated with alterations in the plasma lipid profile and that some lipid fractions in autistic boys may be significantly different than those of healthy boys. A matched case control study was conducted with 29 autistic boys (mean age, 10.1 ± 1.3 years) recruited from a school for disabled children and 29 comparable healthy boys from a neighboring elementary school in South Korea. Fasting plasma total cholesterol (T-Chol), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), the LDL/HDL ratio, and 1-day food intakes were measured. Multiple regression analyses were performed to assess the association between autism and various lipid fractions. The mean TG level (102.4 ± 52.4 vs 70.6 ± 36.3; P = .01) was significantly higher, whereas the mean HDL-C level (48.8 ± 11.9 vs 60.5 ± 10.9 mg/dL; P = .003) was significantly lower in cases as compared to controls. There was no significant difference in T-Chol and LDL-C levels between cases and controls. The LDL/HDL ratio was significantly higher in cases as compared to controls. Multiple regression analyses indicated that autism was significantly associated with plasma TG (β = 31.7 ± 11.9; P = .01), HDL (β = −11.6 ± 2.1; P = .0003), and the LDL/HDL ratio (β = 0.40 ± 0.18; P = .04). There was a significant interaction between autism and TG level in relation to plasma HDL level (P = .02). Fifty-three percent of variation in the plasma HDL was explained by autism, plasma TG, LDL/HDL ratio, and the interaction between autism and plasma TG level. These results indicate the presence of dyslipidemia in boys with autism and suggest a possibility that dyslipidemia might be a marker of association between lipid metabolism and autism.     

Hypocholesterolemic activity of some Indian gums

Indian gums and pectin were added to a diet causing hypercholesterolemia in rats. Gum guar, gum acacia and pectin showed hypolipidemic activity while gum karaya did not. The reduction in serum cholesterol was primarily due to decrease in LDL+VLDL fractions. HDL cholesterol and triglyceride levels were not affected. Increased excretion of fecal steroids was noted with each source of fibre. Trace element content of serum was not affected by these gums but gum karaya and gum guar altered copper and iron and pectin and cellulose altered iron bioavailability.     

Effects of purified eicosapentaenoic acid ethyl ester on plasma lipoproteins in primary hypercholesterolemia.

We investigated the effects of purified eicosapentaenoic acid (EPA) ethyl ester capsules (90% purity), which are free from cholesterol, saturated fatty acids and docosahexaenoic acid (DHA), on plasma lipoproteins and cholesteryl ester transfer protein (CETP) activity. We administered 2.7 g of EPA per day as capsules for 6 months to 14 primary hypercholesterolemic subjects. Total cholesterol, triglyceride and low density lipoprotein (LDL)-cholesterol levels in plasma were significantly reduced. The LDL cholesterol/apoB ratio and LDL particle size did not change. The ratio of high density lipoprotein (HDL)2/HDL3 cholesterol increased from 1.04 to 1.35 (p < 0.05), while the HDL cholesterol level did not change. CETP activity was significantly reduced. The reduction of CETP activity may explain the increase in the HDL2/HDL3 cholesterol ratio. These results suggest that purified EPA not only reduces LDL cholesterol levels but also acts on HDL metabolism in patients with hypercholesterolemia and therefore will be useful for the treatment of hypercholesterolemia.